饲喂吖啶橙对玉米螟赤眼蜂生物学的影响及标记效果

吖啶橙是一种可对昆虫进行标记的染料。本文通过饲喂,考察了吖啶橙对玉米螟赤眼蜂的寿命、产卵量及子代发育情况的影响。结果发现,饲喂吖啶橙延长了蜂的寿命,雌蜂寿命从对照的4.8d显著延长到饲喂低浓度吖啶橙的5.7d,而雄蜂的寿命以饲喂20mg/L吖啶橙的最长,为5.5d。饲喂5和10mg/L吖啶橙溶液的雌蜂6h内的产卵量分别为29.9和30.1粒,略低于对照的34.9粒,饲喂20mg/L的为35.1粒,但各处理与对照间产卵量无显著差异。饲喂吖啶橙对蜂的寄生率、子代羽化率及子代数量均有负面影响。饲喂10mg/L吖啶橙的蜂的寄生率为73.67%,显著低于对照87.83%;饲喂5mg/L吖啶橙的蜂的子代羽化率为96.46%,显著低于对照的99.50%。饲喂5和10mg/L吖啶橙的玉米螟赤眼蜂子代数量分别为(17.1±0.8)和(17.1±1.2)头,显著低于对照的(21.4±0.7)头,饲喂吖啶橙对子代雌性比无显著影响。饲喂吖啶橙24h后,在荧光显微镜下可以观察到吖啶橙的荧光,但由于蜂具有自发荧光,部分饲喂过吖啶橙的蜂不能完全区别于未饲喂的个体。综合考虑吖啶橙对玉米螟赤眼蜂寿命、产卵量和寄生能力的影响以及标记效果,应对吖啶橙进行修饰,或改变观察的理化条件,消除生物自发荧光的干扰,然后用于对赤眼蜂的标记。

Effect of Feeding Acridine Orange on Biological Characteristics of Trichogramma ostriniae (Hymenoptera: Trichogrammatidae) and Its Efficiency as a Labeling Marker

Acridine orange is a dye that can be used to label insect. In this paper, the effect of acridine orange on longevity, fecundity and development of Trichogramma ostrinieae offspring were investigated by feeding the wasps with different concentrations of the dye. The results indicated that feeding the dye prolonged the wasp's longevity. Longevity of females fed 5 mg/L solution of the dye was 5.7 d, significantly longer than 4.8 d in the control. Male wasps fed 20 mg/L solution lived the longest (5.5 d) among three treatments and the control. Fecundities within 6 h were 29.9 and 30.1, respectively, for those fed 5 mg/L and 10 mg/L acridine orange solutions, which were marginally lower than that in the control (34.9) and that (35.1) of wasps fed on 20 mg/L solution. Negative effects of acridine orange were found on parasitism, wasp emergence rate and number of wasp offspring. Parasitism of Corcyra cephalonica eggs was significantly lower in wasps fed 10 mg/L solution (73.67%) than in the control (87.83%). Offspring emergence rate was significantly lower in wasps fed 5 mg/L solution (96.46%) than in the control (99.50%). Number of offspring of wasps fed 5 mg/L and 10 mg/L were (17.1±0.8) and (17.1±1.2), respectively, both significantly lower than that in the control (21.4±0.7). The fluorescence in wasps could be monitored under epifluorescence 24 h after feeding on acridine orange solution. However, because of self-fluorescence in T. ostriniae, it was impossible to distinguish all the unfed wasps from those labeled with acridine orange. So, when the effects of feeding acridine orange on longevity, fecundity and parasitism ability of T. ostriniae and the label efficiency of the dye were considered together, acridine orange could be used as marker to label Trichogramma wasps after being modified or changing physicochemical conditions to eliminate the effects of self-fluorescence of organism.